Gas-cylinder for machine-guns.



H. R. NORTHOVER.

GAS CYLINDER FOR MACHINE GUNS.

APPLICATION FILED NOV-23.1915.

133%,971 Patented July 17, 1917.

HARRY ROBERT NORTHOVER, OF WINNIPEG, MANITOBA, CANADA.

GAS-CYLINDER FOR MACHINE-GUNS.

Specification of Letters Patent.

Patented July 1'7, 1917.

Application filed November 23, 1915. Serial No. 63,104.

To all whom it may concern:

Be it known that I, HARRY ROBERT NORTHOVER, subject of the King of Great Britain, residing at 217 Graham avenue, l/Vinnipeg, Manitoba, in the Dominion of Canada, gunsmith, have invented certain new and useful Improvements in Gas-Cylinders for Machine-Guns, of which the following is a specification.

gas-operated automatic or machine guns of the Colt type, the muzzle end of the detachable and interchangeable barrel is carried in, and connected to the front end of the gun-body by, an arm extending forwardly from the barrel bracket, which arm is disposed below the barrel, and is provided, at its front end, with a sleeve or band wherethrough the said barrel is passed. The bottom of this band and the part of the arm that comes underneath. the same are formed with a gas-cylinder, which when the gun is assembled, registers or communicates with a barrel gas-vent wherethrough the powder-gas pressure acts upon a piston that is contained in the said gas cylinder and is connected with a vertically; swinging gas-lever of the breech mechamsm.

In the Colt automatic gun, the band of the gas-cylinder is made in the form of a solid or rigid sleeve, and the effective automatic action of the gun by the powder-gas, pressure largely depends upon the existence ofa good gas-tight joint between the'barrel vent and the gas-cylinder. To obtain such a good joint as will enable the gun to start working automatically after the first shot, the detachable barrel must be made a perfect fit within the gas-cylinder when the gun is cold, but if such a fit is provided for under these conditions, it becomes a difiicult matter to remove the barrel if the gun requires to be dismounted when hot from continuous firing. On the other hand, unless a good initial fit exists between the barrel and gas-cylinder, it may be necessary before the gun will start working automatically, to fire a succession of shots and to operate the breech mechanism by manually working the gas lever after each shot, in order that the barrel may expand under heat sufiiciently to establish a perfectly tight joint between the barrel-vent and the gas-cylinder.

According to the present invention, and with the object of obviating the above-mentated. That is to say,

tioned disadvantages,

a band which is ex .pansible and contractible and is adapted to be adjusted to or upon the dismountable barrel by mechanical means, whereby a gastight joint can be obtained under all. conditions, while the removal of the barrel, even when the gun is hot, is considerably faciliinstead of providing the gas-cylinder with a barrel-band in the form of a solid rigid sleeve, I construct the same with an adjustable spring-clip or barrel-clamp which is capable of being tightened or slackened by a hand screw or the like, and which can be closed or contracted around the barrel, on the latter being mounted on the gun, so as to establish a sufiiciently gas-tight metal-to-metal joint in the region of the barrel vent to insure that the gun will operate automatically after the firing of the first shot, while on slackening back the screw, the said clamp expands or opens out sufiiciently to admit of the barrel being quickly detached and dismounted.

Figure 1 of the accompanying drawing represents a top plan of a gas-cylinder for a Colt gun embodying an adjustable barrel-band in accordance with my invention.

Fig. 2 is a rear end elevation of the said gas-cylinder.

Fig. 3 is a bottom plan of the same, and I Fig. 4 is a side elevation, showing, in dotted lines, the open-ended passage, or gas-cylinder proper, which is formed in the front end of the body of the device and communicates, in the assembled gun, with the gas-vent in the barrel.

Figs. 5 and 6 are, respectively, a vertical section and a plan view of a modification or development of the invention.

The same letters of reference indicate corresponding parts in the specification and drawings.

In the construction shown, a is the body of the device and b is the band or sleeve wherethrough the barrel of the gun is passed; the circular boss a at the forward part of the said body a being formed with the open-ended passage, or gas-cylinder proper, c for containing the gas-operated piston which is connected with the oscillating lever of the breech mechanism. The upper end 0 of this cylinder opens into the bottom of the barrel-band b and communicates directly with the barrel vent whereih? In accordance with this particular form i of the invention the barrel-band is formed, along its right-hand side, with a split or division 6 and is also provided externally, on the opposite sides of the said split, with a pair of laterally-projecting ears or lugs 6 b pierced with eyes or holes I), b (one plain and the other screwed) to take an adjusting screw d which is furnished with a lever or handle al .the arrangement being such that by rotating the screw in one direction, the split band is contracted or closed around the barrel passing therethrough, whereas by turning the screw in the opposite direction, the said band is permitted to open out or expand by the naturalspring of the metal. A

Thus, when the screw is slackened, the

.dismountable barrel of the gun may be readily passed through the band I) so as to bring its gas-vent into register with the gas-passage 0, after which the contraction or adjustment of the band by means of the levered screw produces a perfectly gas-tight joint between the said band and barrel in the region of the gas-vent cylinder. On the other hand, if it should be required to dismount or remove the barrel when hot from repeated firing, it is merely necessary to slacken the screw to allow the band to expand or open out sufiiciently to permit of the barrel being readily withdrawn.

A gas-cylinder such as above described can be readily fitted to existing 0011; guns in the place of the ordinary solid-band form of cylinder. Or existing cylinders maybe adapted or altered so as to make them adjustable in accordance with my invention by splitting the barrel band and riveting or brazing lugs to take an adjusting screw or bolt to the exterior of the vsaidband, on opposite sides of the split. Figs. 5 and 6 show such an adapted cylinder; 1) being the barrel band, 6 the longitudinal side split or division and b 6 the attached ad ustingscrew lugs which in this particular arrange ment, are riveted to the outside of the band, on the opposite sides of the split.

It is obvious that, instead of the split or division being made at the side of the band as in the illustrated arrangements, the same may be located at the top or any other convenient part; also that any form of screw or bolt may be adopted instead of that shown for mechanically adjusting the said band.

- Having described my inventiom'what I claim and desire to secure by Letters Patent is: i

1. A gas-cylinder for Colt machine guns, embodying an expansibleband or sleeve adapted to encircle the dismountable barrel of the gun and provided with an openended passage for the reception of the gasever piston which opens through the botom of the band and is adapted to directly egister with the gas-vent of the barrel; and means for contracting said band, so as to establish a gas-tight, metal-to-1netal joint between the gas-vent and the piston-receiving passage.

2. A gascylinder for Colt machine guns, embodying an expansible split spring band or sleeveadapted to encircle the dismountable barrel of the gun and provided with an open-ended passage for the reception of the gas-lever piston which opens thr ough the bottom of the band and is adapted to directly register with the gas-vent of the barrel; and means for drawing the ends of the band together, so as to establish a gastight, metal-to-metal joint between the gas- -Vent and the piston-receivingpassage.

3. A gas-cylinder for Colt machine guns, comprising a split band or sleeve adapted to encircle the dismountable barrel of the gun; and means for drawing together the ends of the band, so as to contract said band and thereby establish a gas-tight, metal-tometal joint between the gas-vent of the barrel and the passage which receives thegaslever piston. g g

4. A gas-cylinder for Colt machine guns,

vent of the barrel and the'passage which receives the gas-lever piston. v

5. A gas-cylinder for Colt machine :guns, comprising a split band or sleeve adapted to encircle the dismountable barrel of the gun and provided with laterally-projecting,

apertured lugs at opposite. sides of the split;- and an adjusting member engaged in the ap-.

ertures in said lugs, to draw the latter together, so as to contract said band and thereby establish a gas-tight, metal-to-metal joint betweenthe gas-vent ofthe barrel andthe passage which receives the gas-lever piston. 7 7 V a V U 6. A gas-cylinder for Colt machine guns, comprising a band or sleeve adapted to, en-

circle the dismountable barrel of the gun,

and a rearwardly-extending body portion connected at its forward end to the bottom of said band and having its rear .end adapted for connection to the barrel bracket, said body having its forward end provided with an open-endedpassage for the reception of the gas-lever piston which opens through the said band bottom and is adapted to .di-

rectly register with the gas-vent of the barrel; said band being split transversely at one side thereofand provided at opposite sides of the split with laterally-projecting lugs; and an adjusting member engaged with said lugs to force the same together, so as to contract the band and thereby establish a gas-tight, metal-to-metal joint be tween the gas-vent and the piston-receiving passage.

7. A gas-cylinder for Colt machine guns, Comprising a band or sleeve adapted to encircle the dismountable barrel of the gun, and a rearwardly-extending body portion connected at its forward end to the bottom of said band and having its rear end adapted for connection to the barrel bracket, said body having its forward end provided with an open-ended passage for the reception of the gas-lever piston which opens through the said band bottom and is adapted to directly register with the gas-vent of the barrel; said band being split transversely at one side thereof; and means for drawing the ends of said band together, so as to contract the band and thereby establish a gas-tight, metal-to-metal joint between the gas-vent and the piston-receiving passage.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

HARRY ROBERT N ORTHOVER. lVitnesses:

ARTHUR SADLER, E. J. REUE.

Copies of this patent may be obtained for five cents each, by addressing the commissioner of Patents, Washington, D. 0. 

